Abstract: Systems and methods deliver ultrasound energy to an ultrasound transducer. In one arrangement, the ultrasound energy is delivered at an output frequency that varies over time within a range of output frequencies. The systems and methods select from within the range an operating output frequency for the ultrasound transducer based upon preprogrammed selection rules. The systems and methods can deliver ultrasound energy to the ultrasound transducer at or near the operating output frequency selected, to perform a therapeutic or diagnostic function. In another arrangement, the systems and methods deliver ultrasound energy to the ultrasound transducer at or near a first output power condition to perform a first function, as well as at or near a second output power condition that differs from the first output power condition to perform a second function that differs from the first function.

Abstract: Systems and methods monitor and enable the use of a medical instrument that is configured to be operated in a prescribed manner. The systems and methods employ a use register sized and configured to be carried by the medical instrument, which comprises a memory field for recording a start date and time at an instance of first operation of the medical instrument. The systems and methods also employ a use monitoring controller, which is adapted and configured to be coupled to the use register. The use monitoring controller includes a start validation function that compares the start date and time to a present real date and time and provides a start validation output based upon the comparison. The use monitoring controller also includes an enablement function that enables operation of the medical instrument only if the start validation output meets prescribed criteria.

Abstract: Systems and methods apply audible acoustic energy to cause vasodilation and/or to increase tissue perfusion.

Abstract: Systems and methods stimulate circulatory activity in a targeted body region of an individual by applying ultrasound energy. Before, during or after the application of ultrasound energy, the systems and methods administer an agent to individual that results, e.g., in an angiogenic effect, or in a reduction of blood perfusion, or a chemotherapy effect. The application of ultrasound energy selectively increases blood perfusion or uptake of the agent in the targeted body region.

Abstract: Systems and methods for applying ultrasound energy to a body region. The systems and methods provide an ultrasound applicator including a housing, an ultrasound transducer carried by the housing, and a chamber sized to hold an acoustic coupling media subject to a pressure in acoustic communication with the ultrasound transducer. The systems and methods generate electrical signals to operate the ultrasound transducer to output acoustic energy at a selected intensity level. The systems and methods sense at least one system parameter and compare the sensed system parameter to a desired level. The systems and methods vary the pressure in the chamber based, at least in part, upon the comparison.

Abstract: A medical device assembly and method provides an ultrasound transducer mounted onto a catheter shaft. The ultrasound transducer is mounted such that there is a radial separation between the transducer and the underlying catheter shaft. The transducer is mounted on support structures which do not bridge the gap between the transducer and delivery member. The location of the support structures provides for an “airbacked” transducer that is very efficient and prevents heat build-up in the materials in contact therewith.

Abstract: A medical device assembly and method provides an ultrasound transducer mounted onto a catheter shaft. The ultrasound transducer is mounted such that there is a radial separation between the transducer and the underlying catheter shaft. The transducer is mounted on support structures which do not bridge the gap between the transducer and delivery member. The location of the support structures provides for an “airbacked” transducer that is very efficient and prevents heat build-up in the materials in contact therewith.

Abstract: An ultrasound catheter is disclosed wherein a rotatable transducer couples to the input of a preamplifier. Protection circuits at the input and output of the preamplifier protect the preamplifier from the transducer excitation signal. The preamplifier couples to the distal end of a transmission line. In an alternate embodiment, at least one switch responds to the presence of the transducer excitation signal by coupling the transducer excitation signal to the rotatable transducer and protecting the preamplifier from the transducer excitation signal. The at least one switch responds to the absence of the transducer excitation signal by coupling a received signal produced by the rotatable transducer to the input of the preamplifier. The at least one switch further responds to the absence of the transducer excitation signal by coupling the output of the preamplifier to the distal end of the transmission line.

Abstract: A catheter assembly includes an elongate catheter body having a proximal end and a distal end with a drive cable disposed therein, the drive cable having a proximal end and a distal end, and rotatable relative to the catheter body. A first electro-magnetic element is disposed proximate the distal end of the catheter, and a second electro-magnetic element disposed proximate the distal end of the drive cable and in electrical communication with an operative element mounted at the end of the drive cable, the first and second electro-magnetic elements forming an inductive coupler. The catheter assembly can include various other distal operative elements, which are in communication with corresponding proximal operative elements via transmission lines embedded within the wall of the catheter body.

Abstract: A method of applying a matching layer to a transducer includes placing the transducer on a fixture and covering the transducer with a stencil so that an opening in the stencil allows access to a metal-coated, piezoelectric surface of the transducer, and so that the stencil is affixed to the transducer surface. A roughly cylindrically shaped bead of epoxy is extruded onto the stencil at a predetermined distance from the opening, and a blade is positioned upstanding relative to the transducer surface and located so that the bead lies between the blade and the opening. The fixture is moved laterally so that the blade rolls the bead across the exposed transducer surface to form a layer of epoxy thereon. The fixture can then be moved back in the opposite direction to its initial position if desired. The assembly can also be subjected to a vacuum before the fixture is returned to its initial position. If desired, the fixture can be designed to vibrate during movement.

Abstract: A method of applying a matching layer to a transducer includes placing the transducer on a fixture and covering the transducer with a stencil so that an opening in the stencil allows access to a metal-coated, piezoelectric surface of the transducer, and so that the stencil is affixed to the transducer surface. A roughly cylindrically shaped bead of epoxy is extruded onto the stencil at a predetermined distance from the opening, and a blade is positioned upstanding relative to the transducer surface and located so that the bead lies between the blade and the opening. The fixture is moved laterally so that the blade rolls the bead across the exposed transducer surface to form a layer of epoxy thereon. The fixture can then be moved back in the opposite direction to its initial position if desired. The assembly can also be subjected to a vacuum before the fixture is returned to its initial position. If desired, the fixture can be designed to vibrate during movement.

Abstract: A medical device assembly and method provides an ultrasound transducer mounted onto a catheter shaft. The ultrasound transducer is mounted such that there is a radial separation between the transducer and the underlying catheter shaft. The transducer is mounted on support structures which do not bridge the gap between the transducer and delivery member. The location of the support structures provides for an “airbacked” transducer that is very efficient and prevents heat build-up in the materials in contact therewith.

Abstract: A method of applying a matching layer to a transducer includes placing the transducer on a fixture and covering the transducer with a stencil so that an opening in the stencil allows access to a metal-coated, piezoelectric surface of the transducer, and so that the stencil is affixed to the transducer surface. A roughly cylindrically shaped bead of epoxy is extruded onto the stencil at a predetermined distance from the opening, and a blade is positioned upstanding relative to the transducer surface and located so that the bead lies between the blade and the opening. The fixture is moved laterally so that the blade rolls the bead across the exposed transducer surface to form a layer of epoxy thereon. The fixture can then be moved back in the opposite direction to its initial position if desired. The assembly can also be subjected to a vacuum before the fixture is returned to its initial position. If desired, the fixture can be designed to vibrate during movement.

Abstract: A method of applying a matching layer to a transducer includes placing the transducer on a fixture and covering the transducer with a stencil so that an opening in the stencil allows access to a metal-coated, piezoelectric surface of the transducer, and so that the stencil is affixed to the transducer surface. A roughly cylindrically shaped bead of epoxy is extruded onto the stencil at a predetermined distance from the opening, and a blade is positioned upstanding relative to the transducer surface and located so that the bead lies between the blade and the opening. The fixture is moved laterally so that the blade rolls the bead across the exposed transducer surface to form a layer of epoxy thereon. The fixture can then be moved back in the opposite direction to its initial position if desired. The assembly can also be subjected to a vacuum before the fixture is returned to its initial position. If desired, the fixture can be designed to vibrate during movement.

Abstract: A transducer backing material includes a sticky epoxy resin containing tungsten particles and silver particles. A method of applying a backing material to a transducer includes pouring a mixture of epoxy resin, tungsten particles, and silver particles into a mold containing a layer of piezoelectric material, degassing the mixture, and curing the mixture at a pressure of approximately one atmosphere until the mixture dries.

Abstract: An ultrasound catheter is disclosed wherein a rotatable transducer couples to the input of a preamplifier. Protection circuits at the input and output of the preamplifier protect the preamplifier from the transducer excitation signal. The preamplifier couples to the distal end of a transmission line. In an alternate embodiment, at least one switch responds to the presence of the transducer excitation signal by coupling the transducer excitation signal to the rotatable transducer and protecting the preamplifier from the transducer excitation signal. The at least one switch responds to the absence of the transducer excitation signal by coupling a received signal produced by the rotatable transducer to the input of the preamplifier. The at least one switch further responds to the absence of the transducer excitation signal by coupling the output of the preamplifier to the distal end of the transmission line.

Abstract: An ultrasound catheter wherein a rotatable transducer couples to the input of a preamplifier. Protection circuits at the input and output of the preamplifier protect the preamplifier from the transducer excitation signal. The preamplifier couples to the distal end of a transmission line. In an alternate embodiment, at least one switch responds to the presence of the transducer excitation signal by coupling the transducer excitation signal to the rotatable transducer and protecting the preamplifier from the transducer excitation signal. The at least one switch responds to the absence of the transducer excitation signal by coupling a received signal produced by the rotatable transducer to the input of the preamplifier. The at least one switch further responds to the absence of the transducer excitation signal by coupling the output of the preamplifier to the distal end of the transmission line.

Abstract: A transducer backing material includes a sticky epoxy resin containing tungsten particles and silver particles. A method of applying a backing material to a transducer includes pouring a mixture of epoxy resin, tungsten particles, and silver particles into a mold containing a layer of piezoelectric material, degassing the mixture, and curing the mixture at a pressure of approximately one atmosphere until the mixture dries.

Abstract: A transducer assembly having an improved external connection configuration, a method for manufacturing such a transducer assembly, and a catheter system incorporating the transducer assembly. The improved connection configuration is achieved by creating a conductive path from an upper electrode of the transducer to an electrically conductive notch surface formed on an edge of the transducer assembly so that an external electrical lead can be attached to the active portion of the transducer element via the path.

Abstract: In an intraluminal ultrasound imaging system, ultrasound echoes representing vessel walls are distinguished from ultrasound echoes from blood by detecting and examining the phase of all received ultrasound echoes, extracting selected parameters from the phase information and utilizing the extracted parameters to suppress ultrasound echoes representing blood, thereby to enhance the lumen-to-vessel wall contrast. In a first embodiment, parameters are derived from a phase difference between echoes in approximately the same spatial location, including comparisons between neighboring image vectors of the same image frame or comparison between vectors on successive image frames. Selected parameters may be extracted based on statistics of the phase signal or the phase difference signal or from the slope of the phase difference or the phase signal, either between neighboring image vectors in the same image frame or between images of successive image frames.